There are several methods in use for leak testing parts. One known method consists in evacuating the part under test, putting the evacuated interior of the part into communication with a leak detector and then immersing the outside of the part in a tracer gas. If the part is cracked, the tracer gas penetrates into the part and is detected by the leak detector. However, the part to be tested may not include an orifice for providing access to its interior in order to pump out the vacuum. This is true of electronic integrated circuit packages, for example. The "penetration" method is then used. This method begins by immersing the part to be tested in an atmosphere of tracer gas (usually helium) under a pressure of several atmospheres. The part is then "aired", i.e. it is exposed to air at atmospheric pressure for a while. It is then placed in a sealable container which is connected to a vacuum pump and to a leak detector. If the part is cracked, the helium which penetrated into the crack(s) while the part was immersed in helium under pressure now escapes and is detected.
The invention is thus applicable to leak testing a part which does not have an orifice to provide access to the interior thereof, and more particularly it relates to a machine for performing the leak testing step per se, i.e. to a machine which receives parts that have already been immersed in tracer gas under pressure and then "aired".